Jobs is so closely associated with Apple that investors are afraid the company will flounder, or worse, if Jobs is not around to run things. Tim Cook, Apple's chief operating officer, will handle Jobs' responsibilities during the medical leave, and Jobs will be involved in major decisions.

The news sent Apple's stock, already sagging from concerns about Jobs' ongoing health problems, sharply lower. In the stock market, the prognosis for Apple's shares seems grim. The story in the options market is more nuanced.

Some traders are selling January calls to bet that the stock, now down about $5 in midday trading Thursday to $81, will remain below $85 in the short term.

This explains the rash of trading in January 80 and 85 calls, all of which expire Friday. Similar trading is occurring in the January 80 puts. Clearly, this is opportunistic trading of traders trying to scalp options premium before January options expire, or otherwise salvage whatever value is left in their positions.

In February and beyond, Apple's trading patterns tell a similar story, but trading volumes are much lighter. This suggests that investors are taking a wait-and-see approach until more is known about the impact of Jobs' decision on the company.

J.P. Morgan Securities' Mark Moskowitz told investors this morning that he does not expect Jobs' medical leave to disrupt operations.

"In our view," Moskowitz said, "Mr. Cook and the other members of the Apple management suite have played a critical role in monetizing the vision and mandates of Mr. Jobs in recent years. Here, we do not expect any changes during this difficult period, and we expect the R&D pipeline to remain robust."

For investors who believe the Apple technology phenomenon is bigger than any one man, the options market offers some tempting opportunities. Michael Schwartz, Oppenheimer & Co.'s chief options strategist, likes a 2011 "call spread" that can lead to an investment return of 189%. This strategy is obviously not for traders who don't like committing capital for such a long period.

Schwartz recommends buying January 80 calls that expire in 2011 for $29.95, and selling January 120 calls for $15.75 with the same expiration. The net debit is $14.20. The trade breaks even if Apple's stock trades to $94.20 and has a maximum profit of $25.80.

Apple is scheduled to report fiscal first-quarter earnings Jan. 21. The tenor of this call, arguably more so than the actual results, holds the key to investor sentiment.